• A survey evaluated current and lifetime rates of psychiatric disorders in 533 opiate addicts in treatment at a multimodality program. Information was gathered using a structured interview format, the Schedule for Affective Disorders and Schizophrenia Lifetime version, and the criteria were the Research Diagnostic Criteria. Most were given the diagnosis of at least onepsychiatric disorder in addition to opiate addiction. The most common diagnoses were major depressive disorder, alcoholism, and antisocial personality, and rates of chronic minor mood disorders and anxiety disorders also were found to be elevated in comparison with those found in a community population. In contrast, rates of schizophrenia and mania were very low and did not exceed those reported for the general population. The findings are interpreted as suggesting the importance of detecting and attending to psychopathology associated with opiate addiction.